Centrifugal separator



P. KOMPERT ET AL April 14, 1970 CENTRIFUGAL SEPARATOR 2 Sheets-Sheet 1 Filed May 16, 1968 IyVVENTOgSW a on E BEA/"WWO $1M M55041 April 14, 1970 KOMPERT ET AL 3,506,187

CENTRIFUGAL SEPARATOR Filed May 16, 1968 2 Sheets-Sheet 2 (D N 7 E INVENTORS PIML mapsfir aeggfr 040/0 RIM/M L/MSSou United States Patent 3,506,187 CENTRIFUGAL SEPARATOR Paul Kompert, Stockholm, and Bengt David Ragnar Larsson, Tumba, Sweden, assignors to Alta-Laval AB, Tumba, Sweden, a corporation of Sweden Filed May 16, 1968, Ser. No. 729,797 Claims priority, application Sweden, May 26, 1967, 7,403/67 Int. Cl. B04b 3/04 U.S. Cl. 233-7 6 Claims ABSTRACT OF THE DISCLOSURE The centrifugal rotor contains a conveyor screw operable to discharge sludge, or the like, separated from the feed material supplied to the rotor. At opposite ends of the conveyor screw are shafts detachably coupled to the screw for supporting it in the rotor, and means are provided for journalling these shafts in the rotor. Seals may be located between parts of the rotor and each shaft to shield the bearings of the journalling means against exposure when the separator is disassembled to remove the conveyor screw from the rotor.

The present invention relates to centrifugal separators of the type comprising a rotor and a conveyor screw therein for discharging sludge, or the like, separated from a fluid substance supplied to the rotor.

In prior centrifugal separators of this type, it is not possible to remove the conveyor screw from the rotor without exposing at least one of the bearings by which the conveyor screw is rotatably supported within the rotor. This is an obvious disadvantage of these prior centrifugal separators and makes it hazardous to disassemble the separator, as for cleaning or inspection of the rotor and conveyor screw, because dirt may then enter the bearings supporting the conveyor screw, or these bearings may be damaged in other ways. Also, some of the seals surrounding the supporting bearings may be damaged incident to the disassembling or reassembling of the separator.

The principal object of the present invention is to eliminate this disadvantage of prior separators of the type described above.

According to the invention, the conveyor screw is supported at both ends by means of shafts detachably coupled to the screw and rotatably carried by the rotor. With this construction, the bearings which rotatably support the conveyor screw can be arranged in such a manner that the conveyor screw may be removed from the rotor without exposure of these bearings.

The construction according to the invention also enables a very simplified manufacture of the conveyor screw. It is no longer necessary to provide this screw with means constituting parts of the supporting bearings since it suffices for the screw to have means for its connection with said shafts rotatably carried by the rotor. That is, the bearings supporting the conveyor screw may be arranged in the rotor entirely separated from the conveyor screw itself.

Finally, the invention enables interior cleaning of the separator by disassembling it into a very small number of pieces.

A preferred embodiment of a centrifugal separator made according to the invention is described below with reference to the accompanying drawings, in which FIG. 1 is a side elevational view, partly in section and with parts broken away, of the centrifugal separator in assembled condition, and FIG. 2 is a similar view of the separator in disassembled condition.

The centrifugal separator shown in the drawings com- 3,506,187 Patented Apr. 14, 1970 prises a rotor 1 and a conveyor screw 2 arranged therein for the discharge of sludge, or the like, which has been separated from a substance supplied to the rotor 1. The rotor inlet for the sludge-containing substance is provided by a feed tube 3 extending into the rotor and concentric to the rotor axis. The rotor outlet for sludge separated from the substance is shown at 4, and the outlet for clarified liquid is shown at 5.

The rotor 1, the axis of which extends horizontally, is supported at both ends by means of respective bearings 6,and 6a in which the rotor is arranged to be driven at a predetermined speed. The conveyor screw 2, which is journalled within the rotor, is arranged to be driven at a speed slightly differing from the speed of the rotor. The relative rotary motion between the rotor and conveyor screw is adjusted by means of a planetary gear 7 to which the two rotatable bodies are coupled in a conventional mannerthe rotor 1 by means of a hollow shaft 8 and the conveyor screw 2 by means of a solid shaft 9 extending through the hollow shaft 8.

The conveyor screw 2 is supported within the rotor 1 by meansof two shafts extending into the rotor from its opposite ends and journalled in the end walls of the rotor. One of these shafts is the above-mentioned solid shaft 9 which is journalled by a first means consisting of a combined radial and axial bearing 10 in one end wall 11 of the rotor and by a second means consisting of a radial bearing (not shown) near the supporting bearing 6 of the rotor outside the end wall 11. The other of these shafts is a hollow shaft 12 which is journalled by a first means consisting of a first radial bearing 13 in the other end wall 14 of the rotor and by a second means consisting of a second bearing (not shown) arranged outside this end wall near the other supporting bearing 6a of the rotor.

The conveyor screw 2 is detachably coupled to both of the shaft 9 and 12, and for this purpose the screw is provided at its opposite ends with axially extending bores 15 and 16 adapted to receive these shafts. The shaft 9 and the periphery of the bore 15 for receiving this shaft are provided with interengaging splines 20, while the shaft 12 and the periphery of the bore 16 for receiving this shaft are quite smooth. The fit between the conveyor screw and the shaft 12 is such, however, that the shaft 12 Will be driven when the conveyor screw rotates due to friction between these parts, whereby shaft 12 rotates in its bearings. Of course, a positive driving connection may be provided, if desired, between the conveyor screw 2 and the shaft 12.

Sealing means 17 are arranged around the shaft 9 and are so connected to the rotor wall 11 and so abut the outside of a sleeve 18, firmly connected to the shaft 9, that the bearing 10 between the shaft 9 and the rotor Wall 11 is protected against penetration of the substance which is treated in the rotor. Similarly, the bearing 13 between the shaft 12 and the rotor wall 14 is protected by sealing means 19 connected to the rotor wall 14 and sealingly abutting the shaft 12.

With the above-described construction, it is possible to expose the interior of the centrifugal separator sufficiently for a satisfactory cleaning of the interior, by disassembling the separator into a very small number of piecesand in a manner involving no risk of damaging any sealing means or peneration of dirt into any bearing. Thus, as illustrated in FIG. 2, the disassembly may be effected by first disconnecting the rotor end wall 11 from the main body 1 of the rotor, as by loosening bolts or other releasable means (not shown) connecting those parts. This permits movement of one of the supporting bearings 6 and 6a away from the other and withdrawal of the screw-supporting shafts 9 and 12 from the respective end bores 15 and 16 in the conveyor screw, whereby the latter can be removed from the rotor. Also, after the disassembling operation, the two supporting bearings 16 and 13 are well protected inside the sealing means 17 and 19, respectively. During the disassembling operation, such sealing means need not even be displaced relative to the surfaces against which they seal. The advantages of such an arrangement are obvious.

The centrifugal separator shown the drawing is an embodiment of the present invention chosen only as an example. This embodiment can, of course, be modified in different ways without departure from the inventive idea.

I claim:

1. In a centrifugal separator, the combination of a rotor mounted for rotation about an axis and having an inlet for supplying a substance containing sludge, or the like, said rotor having opposite end portions which are releasable from each other to permit disassembly of the rotor, a conveyor screw disposed in the rotor and operable to discharge sludge separated from said substance, shafts located at said opposite end portions, respectively, of the rotor and detachably coupled to said screw for supporting it in the rotor, and means carried by said end portions of the rotor for supporting and journalling said shafts in the rotor, whereby the conveyor screw is released from said shafts but the shafts remain supported by said end portions when said disassembly is effected.

2. The combination according to claim 1, in which said journalling means include bearings, the combination comprising also means shielding said bearings against exposure when the conveyor screw is so released.

3. The combination according to claim 2, in which said .4 shielding means include seals secured to said opposite end portions of the rotor and sealing against said shafts, respectively.

4. The combination according to claim 1, comprising also spline means through which at least one of said shafts is detachably coupled to the conveyor screw.

5. The combination according to claim 1, in which said journalling means inciude bearing means mounted each end portion of the rotor, each shaft including a screw-supporting part spaced axially from the corresponding bearing means in the direction toward the other shaft and coupled to the screw only by an axially-sliding fit with the adjacent end of the screw, whereby the screw conveyor is released from the shafts by said sliding fits and while said bearing means and shafts are retained in the end portions of the rotor.

6. The combination according to claim 5, comprising also shielding means secured to each end portion of the rotor and sealing against the adjacent shaft at region between its said screw-supporting part and the corresponding bearing, means, whereby the shielding means protect said bearing means from exposure when the conveyor screw is released from the shafts and the disassembled rotor.

References Cited UNITED STATES PATENTS ROBERT W. JENKINS, Primary Examiner 

